summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/i915/i915_gem_gtt.c
diff options
context:
space:
mode:
authorChris Wilson <chris@chris-wilson.co.uk>2016-11-04 10:30:01 +0000
committerChris Wilson <chris@chris-wilson.co.uk>2016-11-04 11:55:39 +0000
commit2c3a3f44dc13a7c964e93385e1c1ca848656bed0 (patch)
treedcc94f3bc020903a2aebfb4d56106623741525cb /drivers/gpu/drm/i915/i915_gem_gtt.c
parenta44342acde304425fa70fd4f06c0e662a79ba5aa (diff)
drm/i915: Fix pages pin counting around swizzle quirk
commit bc0629a76726 ("drm/i915: Track pages pinned due to swizzling quirk") fixed one problem, but revealed a whole lot more. The root cause of the pin count mismatch for the swizzle quirk (for L-shaped memory on gen3/4) was that we were incrementing the pages_pin_count upon getting the backing pages but then overwriting the pages_pin_count to set it to 1 afterwards. With a little bit of adjustment to satisfy the GEM_BUG_ON sanitychecks, the fix is to replace the explicit atomic_set with an atomic_inc. v2: Consistently use atomics (not mix atomics and helpers) within the lowlevel get_pages routines. This makes the atomic operations much clearer. Fixes: 1233e2db199d ("drm/i915: Move object backing storage manipulation") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20161104103001.27643-1-chris@chris-wilson.co.uk Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Diffstat (limited to 'drivers/gpu/drm/i915/i915_gem_gtt.c')
-rw-r--r--drivers/gpu/drm/i915/i915_gem_gtt.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index cad6de65947d..7531bca29f7a 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -3711,6 +3711,13 @@ i915_get_ggtt_vma_pages(struct i915_vma *vma)
{
int ret = 0;
+ /* The vma->pages are only valid within the lifespan of the borrowed
+ * obj->mm.pages. When the obj->mm.pages sg_table is regenerated, so
+ * must be the vma->pages. A simple rule is that vma->pages must only
+ * be accessed when the obj->mm.pages are pinned.
+ */
+ GEM_BUG_ON(!i915_gem_object_has_pinned_pages(vma->obj));
+
if (vma->pages)
return 0;